The present invention relates to a blasting apparatus, a blasting method and a retainer member used for blasting a to-be-blasted object such as a concrete structure or bedrock by supplying electric energy to a fine metal wire for a short time to cause the fine metal wire to rapidly melt and evaporate and then using an evaporation expansion force generated by said melting evaporation of the wire.
Dynamite has been known as blasting apparatus for blasting an object such as concrete or bedrock. However, dynamite is dangerous in view of its handling.
To eliminate such danger, there has recently been proposed a blasting apparatus and method allowing discharge energy to be used.
FIG. 32 shows the above-mentioned blasting apparatus 40, comprising a blasting probe 43 loaded in a loading hole 42 formed in a to-be-blasted object 41 and an electric energy supply circuit 45 for supplying electric energy to a fine metal wire 44 composing this blasting probe 43.
The above blasting proper 43 comprises a blasting vessel 46 inserted in the loading hole 42 in its depth direction and the above fine metal wire 44 connecting the tips of a pair of electrodes 47 and immersed into a blasting substance 48 filled in the blasting vessel 46.
A blasting method for blasting a to-be-blasted object 41 by using the blasting apparatus 40 comprises: forming a loading hole 42 on the surface of the to-be-blasted object 41; loading a blasting probe 43 in this loading hole 42; connecting an electric energy supply circuit 45 to the electrodes 47; and supplying to a fine metal wire 44 for a short time electric energy charged from a power supply device 49 and accumulated in a capacitor 51 via a charging control section 50 by way of discharging.
Then, the fine metal wire 44 rapidly melts and evaporates and evaporatively expands, causing a rapid expansion in volume of the blasting substance 48, whereby the to-be-blasted object 41 is blasted or becomes fragile by the resultant expansion. force.
However, with the above blasting method using the above blasting apparatus 40, since the loading hole 42 for loading the blasting vessel 46 needs be formed in a to-be-blasted object 41, an excessive labor is required therefor. Such labor becomes especially heavy when many loading holes 42 must be formed in the to-be-blasted object 41 as shown in FIG. 33, which consequently requires a great amount of time for the work of blasting the object 41.
Such being the case, as shown in FIGS. 34 and 35, it is considered to employ a blasting vessel 46 placed along the surface of a to-be-blasted object 41 without forming loading holes 42. However, simply placing the blasting vessel 46 along the surface of the to-be-blasted object 41 caused dispersion of the expansion force (indicated by arrowheads in FIG. 35) generated when a fine metal wire 44 expands evaporatively and a blasting substance 48 expands in volume. In this result, the expansion force did not act on the object 41 effectively and could not surely blast the object 41.
It is a purpose of the present invention to provide a blasting apparatus and method capable of solving the above problems and a retainer member used for the same blasting method.
This invention is a blasting apparatus for blasting a to-be-blasted object by supplying electric energy to a fine metal wire for a short time so as to rapidly melt and evaporate the fine metal wire, wherein the fine metal wire is retained in a recess formed on the surface of a retainer member and the recess is placed to oppose the surface of a blasting part of a to-be-blasted object at the time of blasting the to-be-blasted object.
Further, this invention is a blasting apparatus wherein the above recess is filled with a blasting substance which rapidly expands in volume following the melting evaporation of the fine metal wire.
According to the above arrangement, the fine metal wire is disposed in the recess formed on the surface of the retainer member and this recess is pressed against the surface of a to-be-blasted object, so that the preparatory work of forming loading holes in the to-be-blasted object becomes unnecessary and the blasting work can be easily accomplished in a short time.
Besides, this invention is a blasting method for blasting a to-be-blasted object by supplying electric energy to a fine metal wire for a short time so as to rapidly melt and evaporate the fine metal wire, wherein the fine metal wire is retained in a recess formed on the surface of a retainer member, and the recess is placed to oppose the surface of a blasting part of the to-be-blasted object, thereby blasting the object.
Further, this invention is a blasting method wherein the above recess is filled with a blasting substance which rapidly expands in volume following the melting evaporation of the fine metal wires.
Besides, this invention is a retainer member for a fine metal wire used in the blasting method for blasting a to-be-blasted object by supplying electric energy to the fine metal wire for a short time so as to rapidly melt and evaporate the fine metal wire, wherein a groove capable of guiding the fine metal wire is formed on the surface opposing the to-be-blasted object.
Also, this invention is a retainer member for a fine metal wire used in the blasting method for blasting a to-be-blasted object by supplying electric energy to the fine metal wire for a short time so as to rapidly melt and evaporate the fine metal wire, wherein a groove capable of guiding the fine metal wire is formed on the surface opposing the to-be-blasted object, and a recess capable of filling a liquid or semi-solid substance therein is formed on the same surface.
Besides, this invention is a blasting method for blasting a to-be-blasted object by supplying electric energy to a fine metal wire for a short time so as to rapidly melt and evaporate the fine metal wire, wherein the above fine metal wire is retained in a groove formed on the surface of a retainer member, and a liquid or semi-solid substance is supplied into a space between the surface of the retainer member and the surface of a blasting part of the to-be-blasted object at the time of blasting the object by placing the fine metal wire retained in the groove on the surface of the blasting part of the object.
Further, this invention is a blasting method wherein if a crack is present on the surface of the blasting part of the object, the crack is filled with a liquid.
Furthermore, if a crack is present on the surface of the blasting part of the object, the crack is filled with a liquid and then supplied with a semi-solid substance.
Besides, this invention is a blasting method comprising the steps of: fixing a fine metal wire to the press surface of a press member, said fine metal wire being melted and evaporated by supplying electric energy thereto for a short time; applying a blasting substance to the surface of a to-be-blasted object, said blasting substance rapidly expanding in volume according as the fine metal wire melts and evaporates; and supplying electric energy to the fine metal wire for a short time while the fine metal wire is pressed against the surface of the to-be-blasted object by means of the press member.
Further, this invention is a blasting method comprising the steps of: fixing a fine metal wire to the press surface of a press member, said fine metal wire being melted and evaporated by supplying electric energy thereto for a short time; applying a blasting substance to this press surface so as to immerse the fine metal wire therein, said blasting substance rapidly expanding in volume according as the fine metal wire melts and evaporates; and supplying electric energy to the a fine metal wire for a short time while the fine metal wire is pressed against the surface of the to-be-blasted object by means of the press member.
Furthermore, this invention is a blasting method comprising the steps of: pressing a blasting vessel against the surface of a to-be-blasted object by means of a press member with a fine metal wire being sealed in the blasting vessel filled with a blasting substance, said fine metal wire being be connected to a power source; supplying electric energy to the fine metal wire for a short time to cause the fine metal wire to melt and evaporate into evaporative expansion; transmitting the evaporative expansion force of the fine metal wire through the blasting substance to accomplish the blasting of the to-be-blasted object; and forming the blasting vessel using a stretchable material.